Magnetic resonance imaging (MRI) is a bio-magnetic nuclear spin imaging technology developed rapidly along with the development of computer technology, electronic circuit technology, and superconductor technology. MRI uses a magnetic field and a radio frequency pulse to make hydrogen nuclei (H+) of precession in human tissues vibrate to produce a radio frequency signal, and form an image after computer processing. When an object is placed in the magnetic field, the object is irradiated by an appropriate electromagnetic wave so as to make it resonate, then the electromagnetic wave released thereby is analyzed, and the location and type of the nuclei constituting the object may be known, whereby a precise stereoscopic image of the interior of the object may be drawn. For example, an animation of consecutive slices may be obtained by scanning the human brain through magnetic resonance imaging, starting from the head to the foot.
In a MRI system, a transmitting coil transmits a radio frequency pulse to realize magnetic resonance. A local coil receives an analog magnetic resonance signal and sends the analog magnetic resonance signal to a reception coil channel selector (RCCS) and a receiver. The analog magnetic resonance signal is digitized in the receiver. An image reconstruction apparatus uses a digital magnetic resonance signal to reproduce an image.
Currently, there are many types of local coils and corresponding receivers. For example, the patent document with publication number CN103513196A discloses a magnetic resonance receiver and a reception signal processing method and apparatus thereof. The magnetic resonance receiver of the technical solution includes at least two paths of reception channels and at least two analog-to-digital conversion circuits and reception signal processing apparatuses. Besides, the reception signal processing apparatus includes (1) at least two groups of switch units, respectively corresponding to an analog-to-digital conversion circuit, (2) a control unit for controlling the connection of the switch units and the connection of the analog-to-digital conversion circuit, and (3) a composition unit for adding digital signals output from the analog-to-digital conversion circuit that is connected to a working channel.
However, this type of receiver may merely receive a magnetic resonance signal from a certain type of local coil, and may not be compatible with a plurality of types of local coils. If the receiver is required to support other types of local coils, the local coils need to be re-designed, which significantly improves the cost of the system.